Process for canning rice



Patented Nov. 4, 1952 hrs-namin iibbli'catio e Serial No. 207,825" (case-186);

6-;Qlaims.

i Li .1..3 invention relates to: a method .for'prepar-e ing rice for canning and, in particulan atoua pmcess: for precooking and lcanning mice "to: make available riceuimcanned; ready-to seat: form. A 1

.g severalcdifiicultiesa have :in the xpastiprevented the developmentzof asuccesstul canned: rice, and nrincipat among .thesegis .thesfact. :that the sprodnot. when usealed" containers, is; subject :to. a termentation reaction which producesfladarge quantity of gas, thereby render-ingothe"v product notlpnlmunfit sfor: use, sbnt actually, dangerous in aeontainer subject .to;,rupture.;.- Also, the product when lcenned has been.-subj.ect to. deterioration mi -appearance which trendered ;v it. unattractive ofl-nw 'l M- 1.. i. s imagine: 90d containing .a highproportionrof andsismotoriousl-y.dimeultto prepare, 101' the l ose utinousi-starch accompan in the r nul s. w ll; FED-d to; render; the... product sticky. al dssq n whetshauelessa nice oookeddnlajmane ner which leaves the grains firmand-ziindividual aan alii'e fa tive foodzitem;but the-.sticlgysproduct is undesirabl qii for: no ether; reason; .thamits appearance accordjngly; it is: aifundarn ental cbiectf'o fithe insta itiniiem p toapr vide; a processor pr r: ing and canning rice which will ygiveilas a stable Pmdu tsricea of: 500d: pps a ancfirwhicharetains granular-forms It is another object of the invention to provide R '9Q. i: or]. ocaine and: cann n .igice. which w l eave the. grains lar e and stable enou h. to retain their form for an indefinite period :of

time s 1 another object of the invention to provide a process for cooking and canning ricelwhich l zlsatest e; oduct-w h a stable..-s ow-white color.

Other objectsand advantages of the invention will in part be obvious, and in part appear hereinaItei-QI'......

The invention is embodied in the process of preparing and canning ricewherein the rice is subjected to a preliminary cooking operation in a salinesolution, drained, washed, packed in containers' and-the packed rice -aeidified "with 1 a foijd acid "and thecontainer-subsequently sealed d sterilized under;; heatand pressures. 'The invention-accordingly is embodied in the, process involving the steps and'combination of steps involved in preparing, cooking and canning the rice in accordance with the specification here-r inafter set forth.

The requirements of attractive, saleable rice in cans or Jars set standards such that processes in the past have failed a to provide a satisfactory product; 1. 'I hu's; it is known-that: rice graifiSQa-re' accompanied by a superificial coatinganofxrglus tinous starch; which in the cooking operation; will convert the product-t0. a sticky,- unpalatable mass; Accordinglm-in the; preparation: of: rice for canning i-t isidesirable that the riceibe'iwashed free-of this material prior to the initial cooking. Rice is also' peculiarly subject {.to fermentation reactions because blandn'essand high :st'arch content render it highlyattractivezior the growth of molds and bacteria. Gas-producing molds and bacteria particularly have rendered canned-mice an: objectionable. product;. iorsthe islightestr 0011! tamin'ation .of: the unit has .resultedzinzthelproductionof large quantities ofugasawhichrin some. instances have, ruptured the containers; Accords ingly; innthe instant process itheaacidity ornpH of I the preparedzproduct: is: adjustedivtoz-a level which will: inhibit the..development';of this: type of reaction; .1 =11. c1"; .ZQEQI; Otherconsiderations. offthe. market, such as the ,variations: in "weatheri conditiors: :to which the packed: prodfictuwill; be; subjectedi ancl'vthe handling thereof, dictate that:the:;canned grain have-talfirmness which will-becretainedc '3 iThe-.method1 of preparing; ricevfor canning 'is best: understood by; :reference I to a the: following specific.:.example inf. .WhlChiJthB. ratio. of; preferred proportions is reduced: tcrthezpreparationrofa specific .quantity, of."rice:; w: ;ux;;:f.. 1" Iiwo :pounds': of; rice; is cleaned. and: the. dark grains. picked out; The :product: isgrins'ed: 11.03, solution of. detergent, preferably: a. phosphate type-such as sodium hexametaphosphateas05 as to cleanse: the 'surfaces of ;th e grains: from such loose :starch and; glutinous-1. material as 1 may be present rthereon. "Therpreliminaryp rinse serves also as;:.a.. disinfectant to 'ikillv and 'r,emove1.sllchbacteria -.or:mo,ld:sp.ores aasamays be on: the rains; Following. =-.thes..cleansing. and: disinfecting: operation, the rice is rinsed;in-c1ean, :cook-water and allowed to soakzin cool WaterFfOrEa-peri d; about. 10 minutes: A

Three gallons? of: water are brought to= a: boil and the cool, 'soaked,"rice isiadded thereto q uick 1y 1 with agitation; to insure that all the-* g'r'ains individually are contacted byboilin'g water! -Fol.- lowinga period of about three ininutes boilin 8 ounces of salt is added tothe' water-anditheboil ing continued for another 3 minutes. Following this operation, the saline water is poured ofi. The rice, which at this stage is only partially cooked and is characterized by considerably enlarged grains, is packed into containers of about 3 pint size. Glass containers or tin cans are suitable. The two pounds will adequately fill about eight pint size containers.

Each container, which at this time has its portion of rice, has added thereto 1 ounce of citric acid solution (the solution being made up by dissolving 1 ounce of citric acid in 7 ounces of water). The containers are then sealed and passed into retorts where they are steamed at 240 F or 10 pounds of pressure for 25 minutes.

The product thus cooked and canned is characterized by its good, firm appearance and stability in storage, and appears to retain these characteristics for an indefinite period. The grains when thus prepared and removed from the can are large, appear moderately dry, and very white. Samples thus prepared have remained in this condition for several years under harsh weather conditions, extreme changes and rough handling.

Though the example has been given indicating that 2 pounds of rice are cooked in 3 gallons of water, to which are added 8 ounces of salt, and that then the rice is divided into 8 portions for canning, to each pint portion of cooked rice there being added an ounce of citric acid solution, it is to 'be understood that these proportions are not rigid and absolutely critical. Thus, for the boiling operation, ample water should be used to permit free boiling of the rice in an excess of water, so' that the individual grains are cooked and retain their individual form. This is merely gOOd practice in cooking rice and is'dictated by the property rice has of becoming a glutinous mass if it is not cooked in a substantial amount of water.

The proportion of citric acid, stated as 1 ounce i of citric acid solution to each 4 ounces of rice, is a good indication of the degree of acidity desirable for the final packing of rice. The amount of citric acid or other food acids, such as lactic or tartaric, should be enough to renderthe final product sufiiciently :acid to inhibit the growth of anaerobic bacteria or molds, but yet insuflicient to alter the flavor of the product markedly. Since it is anticipated that the product when taken from the packed container or can will be in ready-to-eat form, it is desirable that the acid used for adjusting the final pH be one which is commonly found in foods and, therefore, will have no undesirable effect on the flavor of the product. Citric acid is the commonest but, as indicated, tartaric and lactic acids are related compounds of similar efiectiveness.

Though it is not precisely understood why rice treated in accordance with this process will keep indefinitely and well and retain its appearance, it is believed that the mechanism may be explained somewhat as follows:

When the rice grain has soaked in the cool water, the outer starch cells become slightly soft. Upon being placed in the boiling Water the air Number within the rice grain expand-s, causing it to swell and thereby give it the desirable large size. The critical phase of the process comes about in attempting to stabilize the increase in the size and form of the grain, and yet prevent the loss of moisture therefrom. Also, it is desirable to keep the grains from becoming mushy with additional cooking. It has been found that by adding salt to the cooking water approximately midway in the cookin operation, while the grains are in the process of swelling, accomplishes this effect. The cooking in the saline solution is for a sufiiciently short period so that substantially no salt enters the individual grains. It appears that the effect of cooking in the saline solution is one of sealing the outer cells prior to the passing of the rice into the final containers.

A small quantity of water subsequently added to the rice with the citric acid is sufiicient to enable the grains to stand the added heat of the sterilization operation without becoming dehydrated.

Thus having described the process, it is to be understood that the specific example given 1 is merely to illustrate the sequence of manipulation and that the variation can be carried out in the operation of individual steps and ingredients used without departing from the spirit or scope of the invention.

What is claimed is:

1. A process for canning rice which comprises, rinsing the rice in a detergent solution, soaking the rice in cold water, boiling the rice in a large volume of water, completing the boiling of the rice in a large volume of saline solution, the periods of boiling in water and in salinesolution being consecutive, about equal and from about 2'00 5 minutes duration for each, removing the saline solution, acidulating the rice, adding the rice to containers, and sealing and sterilizing the rice in said containers.

2. The process in accordance with claim 1 in which the total boiling period for the rice does not exceed 10 minutes.

3. The process in accordance with claim 2 in which the acidulation is accomplishedwith a solution of a food acid. 1

4. The process in accordance with claim 2 in which the acidulation is accomplished with citric acid. 7

5. The process in accordance with claim 2 in which the acidulation is accomplished with lactic acid.

6. The process in accordance with claim'2 in which the :ac-idulation is accomplished with tartaric acid.

NORMA BENTON GALLENKAMP.

REFERENCES CITED The following references are of recordin the file of this patent:

UNITED STATES PATENTS Name Date 1,803,605 Fitzgerald 'May 5, 1931 2,187,718 Wilbur Jan. 23, 1940 2,334,665 Malek Nov. 16, 1943 2,400,123 Levinson et al. May 14, 1946 2,434,388 Brehm Jan. 13, 1948 

1. A PROCESS FOR CANNING RICE WHICH COMPRISES, RINSING THE RICE IN A DETERGENT SOLUTION, SOAKING THE RICE IN COLD WATER, BOILING THE RICE IN A LARGE VOLUME OF WATER, COMPLETING THE BOILING OF THE RICE IN A LARGE VOLUME OF SALINE SOLUTION, THE PERIODS OF BOILING IN WATER AND IN SALINE SOLUTION BEING CONSECUTIVE, ABOUT EQUAL AND FROM ABOUT 2 TO 5 MINUTES DURATION FOR EACH, REMOVING THE SALINE SOLUTION, ACIDULATING THE RICE, ADDING THE RICE TO CONTAINERS, AND SEALING AND STERILIZING THE RICE IN SAID CONTAINERS. 